Texas power planners prepare for next freeze

Power grid girds for chillReliability council is paying for added supply of electricity through Saturday

TOM FOWLER, HOUSTON CHRONICLE

Published
6:30 am CST, Tuesday, February 8, 2011

Texas' electric grid operator is preparing for this week's cold spell by lining up more power plant capacity and calling on consumers to conserve energy.

The Electric Reliability Council of Texas said it would pay to have an additional 3,000 megawatts of power plant capacity ready for real-time operations from today through Saturday, when below-freezing temperatures are expected to return to much of the state. That's on top of the approximately 3,000 megawatts of power the state's main grid manager usually has under contract to make sure the grid is stable.

ERCOT Tuesday also called on business and residential customers to conserve electricity during peak usage hours over the next few days — from 6 a.m. to 9 a.m. and from 4 p.m. to 8 p.m.

The moves are designed to avoid a repeat of last Wednesday's power emergency, when more than 50 power generating units went offline unexpectedly due to freezing weather. ERCOT called on local power distribution companies to start rolling blackouts to avoid a systemwide failure. Hundreds of thousands of Texans lost power repeatedly during the day.

ERCOT CEO Trip Doggett said he is not expecting a problem this morning , but officials will monitor the situation carefully. The grid continues to have about 2,700 megawatts of generation capacity unavailable because of unplanned or forced outages.

"Rotating outages are ordered only as a last resort to ensure the security of the statewide transmission grid," Doggett said.

A shortage of natural gas supplies for power plants was cited by some as one of the reasons behind the widespread power plant failures, but on Tuesday an industry official said the state's natural gas producers performed "admirably" last week and that the state never faced a gas shortage. Ron Kitchens, chairman of the Texas Energy Reliability Council, gave the upbeat assessment at a regularly scheduled meeting of the Texas Railroad Commission in Austin.

Wednesday's power use is expected to peak at 54,000 megawatts between 8 p.m. and 9 p.m., while Thursday morning could bring a new winter peak power usage record for Texas of more than 58,000 megawatts between 7 a.m. and 8 a.m. The current winter peak demand record is 56,334 megawatts, set Feb. 2 between 7 and 8 p.m.

Among the conservation efforts ERCOT is suggesting for power customers:

Turn thermostats to 68 degrees or below in the daytime and to 55 degrees at night or when leaving for the day.

Turn off and unplug nonessential lights and appliances.

Avoid running large appliances such as washers, dryers, and electric ovens during peak energy demand hours.

Typically, ERCOT has a minimum of 2,300 megawatts of daily operating reserves scheduled that can be called on at a moment's notice to smooth out imbalances in the system. Typical daily operating reserves are closer to 3,000 megawatts per day, however, with up to another 2,000 megawatts of reserves that can be on line within 30 minutes, said ERCOT spokeswoman Dottie Roark.

These reserves are not the same as the 13.75 percent long-term reserve margin ERCOT aims to keep, which is a measurement of how much total system capacity there is above an expected summertime peak.